Undrafted Rawls mauls 49ers for 255 all-purpose yards

Porous defense Sunday sunk any hopes of the 49ers upsetting the Seahawks on the road, as Seattle completed the season sweep against their NFC West rivals with a 29-13 victory at CenturyLink Field.

Missed tackles and the inability to contain bruising young running back Thomas Rawls led to 29 Seattle points on a season-high 508 yards of offense against Jim Tomsula’s defensive unit.

Rawls finished the day with 255 all-purpose yards, good for two of Seattle’s four touchdowns. The other two scores would come at the hands of rookie receiver Tyler Lockett, who nabbed his touchdowns on four receptions for 48 yards.

The lapse in defense overshadowed what was an otherwise solid performance from QB Blaine Gabbert, who threw for 264 yards on 22-of-34 attempts and a touchdown in his first career start in Seattle.

The loss sinks the 49ers to 3-7, extending San Francisco’s winless streak on the road against the Seahawks (5-5) dating back to December 2011.

WR Anquan Boldin fought through hamstring troubles to lead the 49ers with 93 yards receiving. Tight end Vance McDonald caught his first-career touchdown pass for the 49ers sole trip into the end zone during the closing seconds of the first half.

The absence of RB Marshawn Lynch didn’t prevent the Seahawks from going beast mode on the 49ers early, as a pair of young players had their way with the 49ers defense to give Seattle an early lead.

Exploiting the loss of NT Glenn Dorsey, Rawls bullied his way through the 49ers defensive line for nearly 100 yards rushing in the first half, helping to push his team into scoring range during their first three trips on the field.

Lynch’s understudy would also work his way into the end zone for the Seahawks’ second touchdown of the game on a two-yard plunge to give Seattle a 14-0 lead in the first quarter.

But even with Rawls’ fleet-footed outburst, it was Lockett who stole the first-half show on offense. Lockett made his mark on the Seahawks’ inaugural drive, burning DB Jimmie Ward for a 24-yard touchdown to break open the afternoon’s scoring.

Lockett’s second score would be no less impressive, as the 182-pound receiver dragged the hard-hitting S Jaquiski Tartt five yards into the end zone to give Seattle a 20-0 lead later in the second.

Meanwhile, Gabbert and the 49ers offensive unit looked to shake off some bye week rust, as the team looked lost while trying to move the ball early on.

After a series of three-and-outs left the 49ers with a scoreless 28 minutes of play, Gabbert would finally turn things around, leading his team on an impressive 2-minute drill to avoid a first-half shutout.

Working a variety of dump-offs and throws to his receivers, the fifth-year quarterback pushed his offense 92 yards down the field on just nine plays before connecting with McDonald on a 19-yard seam route to cut the deficit to 13 before heading into the locker room.

San Francisco would ride their offensive momentum into the third quarter, as Gabbert would tack on a pair of consecutive scoring drives — both ending in Phil Dawson field goals — to further cut into the Seahawks lead.

Gabbert would continue to look for his tight ends McDonald and Garrett Celek — whom the Seahawks had struggled in picking up all game — to lead his team to 110 total yards in the frame, heading into the fourth quarter with just a 10-point deficit.

Seattle would jump back out to a comfortable lead however, as a combination of Rawls and poor tackling led to the running back’s second touchdown of the game on a 31-yard dump off across the middle of the field.

The score would further shift momentum away from San Francisco, as Gabbert was unable to mount a rebuttal throughout the remainder of the game.

The outing was yet another tough pill to swallow for the 49ers, who continue to see this once fierce rivalry grow into a lopsided affair.

The lone bright spot in Sunday’s contest may have been the encouraging play of Gabbert, who performed admirably against a tough Seattle secondary.

Gabbert’s final line may have not been blistering, but the quarterback looked to make solid reads while showing poise in the pocket throughout the game. He wasn’t devoid of his questionable moments, as a couple near interceptions-including one on the goal line- could have made his stat line less favorable.

But Gabbert kept the game competitive heading into the fourth quarter. He’s almost certainly not the future of the franchise, but he looks to be a solid fill-in for the remainder of the season.